The present study aimed to evaluate stress radiography and magnetic resonance imaging (MRI) findings in medial meniscus posterior root tears (MMPRTs).
The study included 27 patients (26 females, mean age, 53.52 years) who underwent high tibial osteotomy and in whom medial menisci were concurrently examined arthroscopically. Preoperative stress radiographs and MRI series in 14 cases with root tears (MMPRT group, detected arthroscopically) and in 13 cases without tears (control group) were evaluated. Joint spaces measured on the stress radiographs were compared between the operated and opposite knees in each group.
On the varus stress radiographs, the mean lateral joint space of the operated knees was significantly wider than that of the opposite knees in the MMPRT group (P = 0.007). Upon MRI studies, meniscal extrusion was significantly more common in the MMPRT group than in the control group. Moreover, the amount of meniscal extrusion was correlated with the tear size.
Widening of the lateral joint space on the varus stress radiography was higher in the cases with root tears. Therefore, we propose that stress radiographs can be helpful in the diagnosis of MMPRT.